Scientists at Tufts University conducted an observational study of 549 men and women with an average age of 75 who were split into five groups based upon individual Vitamin B-12 levels. The study looked at cognitive performance of each individual over eight years using results of a periodical dementia screening test called a Mini- Mental State Examination (MMSE).
The groups with the lowest and second lowest B-12 levels showed much greater mental decline than those with higher levels. The dementia test scores dropped .24 points per year in individuals with higher B-12 levels, while scores for the two lowest B-12 groups dropped .35 points annually. Martha Savaria Morris, an epidemiologist at Tufts University, said the results showed that even a small B-12 deficiency can seriously affect cognitive health:
Men and women in the second lowest group did not fare any better in terms of cognitive decline than those with the worst vitamin B-12 blood levels. Over time, their MMSE scores declined just as rapidly. Rapid neuropsychiatric decline is a well-known consequence of severe vitamin B-12 deficiency, but our findings suggest that adverse cognitive effects of low vitamin B-12 status may affect a much larger proportion of seniors than previously thought.
Eggs and lean meats offer good dietary sources of B-12, but many older adults have difficulty absorbing vitamins from food, which is why some researchers and health professionals suggest taking a daily vitamin B supplement.
Writer Bennett Holleman contributed this report.